[wpilibj] Consistently use ErrorMessages.requireNonNullParam (#4776)

Also remove wpilibj version of ErrorMessages and consistently use static import.

wpiutil/src/test/java/edu/wpi/first/util/ErrorMessagesTest.java

@@ -0,0 +1,24 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+package edu.wpi.first.util;
+
+import static edu.wpi.first.util.ErrorMessages.requireNonNullParam;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+class ErrorMessagesTest {
+  @Test
+  void requireNonNullParamNullTest() {
+    assertThrows(
+        NullPointerException.class, () -> requireNonNullParam(null, "testParam", "testMethod"));
+  }
+
+  @Test
+  void requireNonNullParamNotNullTest() {
+    assertDoesNotThrow(() -> requireNonNullParam("null", "testParam", "testMethod"));
+  }
+}